This function calls icu::BreakIterator::createLineInstance() but does not clean up after it.
Instead use a static instance that is cloned (for thread-safety) and deleted as necessary.
(cherry picked from commit 6d276698b6)
This means we have RTL support again with ICU 58+. It makes use of:
- ICU for bidi-itemization
- ICU for script-itemization
- OpenTTD for style-itemization
- harfbuzz for shaping
